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Offline Backups

An offline backup is where the data or system that is backed up is unavailable for other uses for the duration of the backup. In database circles, these types of backups are referred to as cold backups.

24/7 Availability

As is implied by its name, this results in an outage on the data and application(s) using that data and will take as long as the backup takes to complete. This presents obvious disadvantages for 24/7 businesses that cannot be denied. However, in applications or businesses where 24 Ă— 7 availability is not required, there are some advantages to offline backups, most typically where there are no dedicated IT staff to perform more complex recoveries that may arise from other forms of backup.

Pricing

Such backups can be cheaper, too. For some enterprise products, database backups will be a licensed feature*: businesses may enact a policy whereby hot/online backups are performed for production databases, but development and test databases requiring backup are instead shutdown.

Potential Performance Problems

Offline backups may actually cause performance problems outside of the backup window. Many modern enterprise applications, particularly databases, use sophisticated caching techniques to reduce the number of IO operations required, with SAP and Oracle being two such applications. As soon as an application is shut down, any cache it may have been maintaining is typically lost. Indeed, some vendors will strongly recommend against frequent restarts of their applications for cache performance reasons.

Advantages of Offline Backups

The advantages of offline backups include the following:

The disadvantages of offline backups include the following:


Published on Fri 14 October 2016 by Manny Larson in Computer Science with tag(s): backup